Fatigue in High and Very High Frequency Manual Lifting, Lowering and Carrying and Turning

This paper presents the results of a study undertaken to determine the perceived exertion and physiological responses of highly trained and experienced workers to high (up to 16 repetitions per minute) and very high frequency (above 16 repetitions per minute) manual lifting, lowering, and carrying and turning tasks. The results indicate that workers engaged in such highly repetitive and physically demanding tasks operate at work loads that may clearly be considered physically fatiguing and unacceptable by the current physiological design criteria. The workers, however, perceived these exertions to be generally acceptable. The physiological responses of the workers are also compared with previous and recommended physiological design criteria.